WO2016193595A1

WO2016193595A1 - Rearing support and oyster rearing method

Info

Publication number: WO2016193595A1
Application number: PCT/FR2016/051271
Authority: WO
Inventors: Florent Tarbouriech; Pierre Henri GALAVIELLE
Original assignee: Medithau
Priority date: 2015-05-29
Filing date: 2016-05-27
Publication date: 2016-12-08
Also published as: FR3036581A1; FR3036581B1

Abstract

An oyster rearing support that has a body (4) having a portion (20) for rearing an oyster, said portion (20) being substantially flat and comprising an area for the attachment of a juvenile oyster and at least one hole (16) opening on either side of the body (4) at a distance from said attachment area, such that the oyster comes to grip onto the support at said hole during the growth of same.

Description

Breeding support and oyster farming method

The invention relates to the field of oyster farming. Oyster culture is a traditional and complex field that has changed little over time. Traditionally, oysters are reared in an uncontrolled manner, either directly on the ground or in devices such as submerged pockets in the wild or baskets or lanterns. In some areas, oysters are stuck with cement on ropes or bars.

The Applicant has already developed several innovations for the purpose of modernizing and improving the zootechnie oyster. For this purpose, it has for example proposed the application FR1453555 which describes an oyster farming process to greatly improve the organoleptic qualities of oysters.

During her research, the Applicant has found that it is very difficult to influence the oyster form factor. She also found that it is very difficult for consumers to confidently identify the oysters they buy. Indeed, apart from their confidence in the labeling of the hamper and the knowledge for a very limited number of consumers of the taste qualities of the different oysters, it is not possible to confidently qualify the provenance of an oyster.

To solve these problems, the Applicant has invented an oyster farming medium described in the application FR1455418. When the portion receiving oysters is concave, the Applicant has found that oysters adopt an unnatural form factor. In fact, in the wild, when oyster larvae catch on a rock, they develop by following the shape of the rock. It has therefore sought to use supports whose surface is generally flat, to allow oysters to develop in their natural form.

However, this breeding medium does not offer optimal yield. Indeed, when the portion of the breeding medium that receives an oyster is substantially flat, the Applicant noticed that some oysters have a tendency to reject the glue after a while, breaking off during breeding and are lost. To fill this problem, a larger amount of glue can be used, but it then becomes very difficult to harvest the oysters, that is to say to detach them from the support.

The invention improves the situation. For this purpose, the invention provides an oyster culture support, which has a body having a portion for rearing an oyster, which portion is substantially flat and comprises a juvenile oyster attachment zone and at least a hole opening on either side of the body away from said attachment zone, so that the oyster hooks on the support at said hole during its growth.

This type of support is very advantageous because the oyster, growing up, can grow through the hole and form a shell rivet that passes through the body of the support. Thus, the oysters are firmly attached to the support and are no longer lost. In addition, since the rivet is made of crystallized calcium carbonate (CaCO 3) (calcite and aragonite), it is relatively easy to break by shear stress, which makes harvesting much simpler. In a variant, the support of the invention may have one or more of the following characteristics:

the portion has at least two holes opening on either side of the body at a distance from said attachment zone so that the oyster hooks on the support at the level of said holes during its growth,

the portion comprises four substantially aligned holes opening on either side of the body at a distance from said zone of attachment of the body, which body has another portion substantially flat and opposite to the portion, where said holes open,

the attachment zone receives a point of glue for attaching the juvenile oyster,

the glue point passes through at least one hole to form a rivet,

the portion receives another point of glue on the part of the body where said hole opens,

the portion has a mark forming a relief in the body, and - The body has a set of holes opening on either side of the body at one or both ends of the latter.

The invention also relates to an oyster culture method which comprises:

attaching one or more juvenile oysters to a portion of a support according to the invention,

- apply a rearing step to the oyster (s) so attached for a period of between 6 and 48 months,

- detach the oysters from their respective portions.

Alternatively, juvenile oysters are attached on either side of the body of the support.

Other features and advantages of the invention will appear better on reading the following description, taken from examples given for illustrative and non-limiting purposes, taken from the drawings in which:

FIG. 1 represents a perspective view of a support according to the invention,

FIG. 2 represents a partial top view of the support of FIG. 1, and

FIG. 3 represents a cross-sectional view of the support of FIG. 1, on which two oysters are received on either side of the support at the beginning of rearing,

FIG. 4 represents a sectional view of a variant of the support of FIG. 1, on which two oysters are received on either side of the support at the beginning of the breeding, and

- Figure 5 shows a view similar to that of Figure 4, with an oyster at the end of breeding. The drawings and the description below contain, for the most part, elements of a certain character. They can therefore not only serve to better understand the present invention, but also contribute to its definition, if any.

Figure 1 shows a perspective view of a support according to the invention. As can be seen in this figure, the support 2 comprises a body 4 of substantially parallelepipedal shape similar to an elongate bar. As will be seen in the following, the support 2 is able to receive oysters on either side of its body 4 on surfaces respectively referenced 6 and 8. Thus, the portion of the support 2 on which the oysters are attached is substantially flat, which poses problems maintaining the attachment between the oyster and the support during breeding. In the example described here, the body 4 has a length of about 2.7m, a width of 70mm and a thickness of 5mm. The body 4 is here made of low density polyethylene (for example the PE-W orthopedic product commercially available), and is adapted to be connected to an oyster farming structure as described in the patent FR1003249 or on a structure of standard breeding.

Alternatively, the body 4 may have a length of between 40mm and several meters, a thickness of between 2mm and 10mm, and in particular between 2mm and 6mm when it is low density polyethylene, depending on the compromise between flexibility and robustness.

The body 4 may also be made of PVC (polyvinyl chloride), silicone, PE (polyethylene), wood, steel (or any other metal or alloy resistant to the marine environment) or any other suitable material. The breeding can be carried out in suspension or not: the supports 2 can be laid flat in clear, or on pocket tables, lanterns, baskets or any other breeding device.

The body 4 is pierced with a plurality of through holes. In the embodiment shown in Figures 1 to 3, these holes are of two types. A first set of holes, designated by reference numeral 10, is used to hook support 2 to the breeding structure. A second set of holes, including a plurality of hole sets each designated by reference numeral 20, is used to maintain oysters on the support 2 during breeding.

As can be seen in Figure 2, in the example described here, the support 2 has two first sets of holes 10, each provided at the respective ends of the body 4. Each first set comprises five holes having a diameter of about 8mm . The five holes are arranged in the form of four holes 12 whose centers define a rectangle substantially 25 mm from the end of the body 4 and substantially centered on the width of the body 4. This rectangle has a length of about 50 mm and a width of about 40mm, so that the centers of the holes 12 are each at a distance of about 15mm from the longitudinal edge of the body 4. Between the four holes 12, a fifth hole 14 is provided, substantially centered relative to the width of the body 4, and at a distance of about 30mm from the end of the body 4.

The holes 12 and 14 are arranged such that when the support 2 is attached to a breeding structure, the oysters that are attached to the support 2 experience fewer jolts, and are less likely to detach. Indeed, the support can be attached by two holes 12 aligned along the length of the support, or by a hole 12 and the hole 14. Thus, the support 2 offers little grip to the rotation due to wind. Hole 14 can also be used to center support 2 in other steps such as oyster sticking or harvesting.

Alternatively, other arrangements could be provided for the holes of the first set, and the support 2 could have only one first set or not at all for example in the case where the support comprises a single set of holes in the second set of holes.

As can be seen in FIG. 2, in the example described here, each set of holes in the second set comprises four holes 16 having a diameter of approximately 5 mm, substantially aligned in a direction perpendicular to the length of the body 4. According to FIG. in this direction, the center of the most extreme holes 16 is located about 8mm from the longitudinal edge of the body 4, and the centers of the holes 16 are spaced two by two by about 18mm. Alternatively, the holes 16 could also be aligned in the direction of the length of the body 4, for example when the support 2 comprises only one set of holes 16. In addition, the holes 16 could have a larger diameter, between 2mm and 8mm. In the example described here, between each hole 16 the most extreme and the hole 16 adjacent thereto, the body 4 has a mark 18 in the form of indentation. In the example described here, this mark 18 represents a capital H whose one of the bars constitutes the bar of a capital T. The mark 18 has a thickness of about 1 mm, a depth of about 0.5 mm, and a width of about 15 mm for a height of about 18 mm. The terms "height" and "width" are here used with reference to the longitudinal direction of the body 4, that is to say that the width of the mark 18 is substantially parallel to the alignment direction of the holes 16. D Other dimensions, patterns and / or orientation may be used for the mark 18.

As has been described in patent application FR1455418 the mark 18 has the advantage that the oyster, growing up, comes to marry its shape, and naturally burn the negative of the mark 18 in its shell. Thus, in the example described here, the shell of the oyster will have a rib about 0.5mm in height, with the letters H and T in uppercase letters.

The Applicant has discovered that the use of extremely smooth polyethylene makes it possible to offer the oyster a very high quality of etching, as well as easy stain removal. The mark 18 can have virtually any dimension, the work of the Applicant having demonstrated that even marks of a few hundred micrometers in thickness and / or depth are functional with a material such as that used in the example described here . The mark 18 may also be a rib, in which case the oyster will have a throat mark in its shell.

Alternatively, the body 4 may be devoid of mark 18, it does not play an important role in the attachment of the oyster support 2 since it has a thickness and a depth less than 5mm. Thus, the holes 16 and the part of the body 4 delimited by the mark 18 define a portion 20 on which an oyster is attached to the support 2. In the example described here, the centers of the holes 16 of adjacent holes are spaced apart. about 45mm. This spacing may vary depending on the density of breeding sought and the breeding techniques used.

As can be seen in FIG. 3, the production of four holes 16 makes it possible to use the support 2 in a reversible manner: an oyster 22 is received on the surface 6 at the holes 16 located furthest to the left, while an oyster 24 is received on the surface 8 at the holes 16 located furthest to the right.

In the example described here, oysters 22 and 24 are mirrored with respect to one another. At the beginning of breeding, the juvenile oysters are stuck at the level of an extreme hole 16 at the beginning of the breeding so that their hinge is the part closest to the longitudinal edge of the body 4. Thus, the oysters 22 and 24 will grow "inwards" of the support 2, and gradually join the other holes 16. In the example described in Figure 3, the body 4 has an adhesive point 26 on each of the surfaces 6 and 8. The point of glue 26 covers and passes through two of the holes 16, so that it forms a rivet with two nipples 28 in the opposite surface. Thus, the oyster stuck on the glue point 26 is initially held on the support 2 by the latter, which defines a zone of attachment of the juvenile oyster, then growing, it will cling to both nipples 28 of the glue point 26 of the other surface. Thus, if the oyster "rejects" part or all of the glue point 26, it will remain attached to the support 2 by means of the nipples 28 of the glue point 26 on the other side of the body 4. Thus, the zone attachment of a juvenile oyster on the face 6 serves as hooked for an oyster attached to the face 8, and vice versa.

The Applicant has also discovered that the holes 16 allow many variants to hang the oysters even more reliable than the nipples 28 in glue. Indeed, as can be seen in Figure 4, using an adhesive point 26 which does not cover the holes 16, and placing the juvenile oyster close to them, it is the oyster itself. same who will make two rivets through the holes 16 while growing up. Thus, even if the oyster 22 or 24 rejects the glue of the glue point 26, the rivets formed by its shell will keep it attached to the support 2, as can be seen in FIG. 5. According to this variant, the fastener the oyster is maximum at the end of breeding, and easy stain removal because it is enough to cut the two rivets in limestone. The attachment zone of the juvenile oyster is therefore not formed here at the level of the hole 16, and these are located at a distance from the attachment zone so that the growing oyster will use the holes 16 to make with its shell rivets calcium carbonate.

Alternatively, the point of glue 26 may be provided to cross only one hole 16, the oyster forming a rivet through the second hole 16 growing. According to this variant, the attachment of the oyster is safer at the beginning of breeding thanks to the glue rivet. In this variant, it is also possible to make a mark at the glue point 26, so that both the glue point and the oyster are marked, or one of them only.

According to other variants, the oysters may not be disposed on either side of the body 4, or may be with an offset along the length of the support 2. In addition, as described above, the body 4 may comprise a portion 20 or more, spaced according to the desired breeding densities and breeding techniques used.

In the examples described here, the portion which serves to rear the oyster on the support 2 has a zone of attachment for the juvenile oyster, and at least one hole at a distance from this zone, which allows the oyster to cling to the support during its growth, whether around a rivet of glue through this hole, or whether it is by forming a rivet by the oyster as such through this hole .

With the support 2, the oysters can therefore grow with a natural form factor, while being marked if the portion 20 has a mark 18. Thanks to the rivets formed either by the glue or by the oyster, the attachment to the support is greatly improved, and little or no oysters are lost during breeding. In addition, thanks to the optional presence of the first set of holes, it is possible to raise in suspension, or in a traditional way. Finally, thanks to the design described above, the support 2 is symmetrical, which avoids the need to use a keying and allows to use it industrially for the oysters of the young oysters and the harvest of oysters at the end of breeding. Thanks to the support of the invention, it is possible to implement an oyster culture process in which juvenile oysters are attached to a support according to the invention, and immersed for a period of between 6 months and 48 months. It should be noted that any type of immersion process may be considered, whether it is a culture site with a natural tide, or whether it is a culture site in which there is no natural tide. In particular, the breeding method which is the subject of the patent application FR1453555 allows, in conjunction with the support 2 of the invention to obtain oysters with exceptional organoleptic qualities. The breeding medium according to the invention is suitable for any type of oyster, whether hollow or flat. In general, oysters belonging to the following species are considered: ANIMAL Rule; MOLLUSC branch; Class BIVALVE; Subclass PTERIOMORPHE; Order OSTREOIDA; OSTREIDAE families; Genres Ostrea, Crassostrea, Ostreola, Saccostrea, and other genera of this family.

Claims

claims

Oyster farming medium, characterized in that it has a body (4) having a portion (20) for raising an oyster, which portion (20) is substantially flat and comprises an attachment zone of juvenile oyster and at least one hole (16) opening on either side of the body (4) at a distance from said attachment zone, so that the oyster clings to the support at said hole during his growth.

Support according to claim 1, wherein the portion (20) has at least two holes (16) opening on either side of the body (4) away from said attachment zone so that the oyster comes s' hanging on the support at said holes during its growth.

Support according to one of the preceding claims, wherein the portion (20) comprises four holes (16) substantially aligned opening on either side of the body (4) away from said body attachment zone (4), which body (4) has another portion (20) substantially flat and opposite to the portion (20), where the said holes (16) open.

Support according to one of the preceding claims, wherein the attachment zone receives a glue point for attaching the juvenile oyster.

The support of claim 4, wherein the glue point passes through at least one hole (16) to form a rivet.

Support according to claim 4 or 5, wherein the portion (20) receives another point of glue on the part of the body (4) where opens said hole (16).

Support according to one of the preceding claims, wherein the portion (20) has a mark (18) forming a relief in the body (4).

Support according to one of the preceding claims, wherein the body (4) has a set of holes opening on either side of the body (4) at one or both ends of the latter.

Oyster farming method comprising the following operations:

- attaching one or more juvenile oysters to a portion of a support according to one of the preceding claims, - apply a rearing step to the oyster (s) so attached for a period of between 6 and 48 months,

- detach the oysters from their respective portions.

10. The method of claim 9, wherein juvenile oysters are attached on either side of the body of the support.